A drill guide for use in compression osteosynthesis is disclosed in EP-B1 0 173 267. In this drill guide the actual drill bushing is positioned eccentrically, so that a pre-determined compression effect can be achieved.
A disadvantage of this drill guide is that it pays insufficient attention to the geometry of the shank of the screw to be inserted. The plate end of this known guide merely simulates the geometry of the head of the screw to be inserted. This can be inadequate when the hole to be bored is oblique to the plane of the compression plate. Another disadvantage is that the known drill guide permits the execution of eccentric bores only, and thus makes it necessary to use another guide for neutral screw positionings. With conventional drill guides it is not possible to achieve a spherical seating in the screw hole, so there is no guaranty of a stress-free osteosynthesis, that is, one that is free from parasitic additional loads.